good enough

src/dev/framebuffer/console.rs

@@ -4,18 +4,18 @@ use crate::trafficcontrol::TrafficControl;
 
 pub struct FramebufferConsole {
     pub buffer: [[char; 20]; 15], // our font is 16x16, 320x240 is the standard res, so 20x15
-    pub cursor: (usize, usize), // (x, y)
+    pub cursor: (usize, usize),   // (x, y)
+    pub need_screen_clear: bool,
 }
 
-pub static FBCONSOLE: Spinlock<FramebufferConsole> = Spinlock::new(
-    FramebufferConsole::empty()
-);
+pub static FBCONSOLE: Spinlock<FramebufferConsole> = Spinlock::new(FramebufferConsole::empty());
 
 impl FramebufferConsole {
     pub const fn empty() -> Self {
         Self {
             buffer: [[' '; 20]; 15],
             cursor: (0, 0),
+            need_screen_clear: true,
         }
     }
 
@@ -26,10 +26,12 @@ impl FramebufferConsole {
             self.buffer[line_num] = copy_from;
         }
         self.buffer[self.buffer.len() - 1] = [' '; 20];
+        self.need_screen_clear = true;
     }
 
     // DOES send a framebuffer update!
     pub fn clear_terminal(&mut self, tc: &mut TrafficControl) {
+        self.need_screen_clear = false;
         self.buffer = [[' '; 20]; 15];
         self.cursor = (0, 0);
         self.render(tc);
@@ -52,6 +54,7 @@ impl FramebufferConsole {
             if c == '\x08' {
                 was_special_char = true;
                 // we don't clear the character, that's up to the terminal
+                self.need_screen_clear = true;
                 if self.cursor.0 > 0 {
                     self.cursor.0 -= 1;
                 } else {
@@ -79,8 +82,11 @@ impl FramebufferConsole {
         self.render(tc);
     }
 
-    pub fn render(&self, tc: &mut TrafficControl) {
-        fb_clearscreen(tc);
+    pub fn render(&mut self, tc: &mut TrafficControl) {
+        if self.need_screen_clear {
+            fb_clearscreen(tc);
+            self.need_screen_clear = false;
+        }
 
         for (y, line) in self.buffer.iter().enumerate() {
             fb_write_char_array(tc, 0, y * 16, line);